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Monday, March 25, 2013

Comment on the role of formal logic in English law.

Q. What are the Comment on the role
of formal logic in English law.

Answer plan:

It is important to differentiate
‘formal logic’ and ‘legal reasoning’. The former involves a scientific approach
to problems of induction and deduction; the latter is an imprecise description
of a common attitude to the determination of a legal dispute. The answer ought to
show how far formal logic is used in a judgment, and attention should be
directed to some of the problems involved in attempts to apply a rigid system
of rules to legal procedure. The following skeleton plan is used as a framework
for the answer:

Introduction –
definition of logic – its restricted use in law –

the
Aristotelian syllogism – inflexibility of formal logic –

reasoning in
adjudication – references in judgments to logic – argument by analogy – logic
and prevention of

inconsistency
– arguments concerning logic and control –

Dewey’s
warning on logic and law – the danger of

abandoning
logic in the law – conclusion referring to the

‘Hand formula’
and jurimetrics.

Answer

We define logic, for the purposes of
this answer, as a science that is concerned with the canons and criteria of validity
in thought and demonstration. It is a methodology, a technique, enabling conclusions
to be drawn from information presented in a specific, prescribed manner. In
English law, it plays a restricted role and is never used as the sole rationale
of a legal decision, so that it is unlikely for a judgment to rest on the
belief that the ‘plaintiff has demonstrated the logical superiority of his
case’. Almost invariably, its use is qualified, as will be illustrated below. Reference
will be made to those who believe that an extended use of logic, as the basis
of a scientific approach to the law, is desirable.

There are several different types of logic; in Europe, Aristotelian
logic is dominant. Aristotle taught that logic was ‘the science of sciences’,
that is, a methodological introduction to the other sciences. It necessitated ‘thinking
about thinking’ and involved a system of rules by which deductive thought might
be represented and analysed. The essence of deduction involves the derivation
of a conclusion from a set of statements (‘premises’). Aristotle advocated the
use of the syllogism – a formal scheme of demonstration. A simple example is as
follows: (1) All A is B; (2) Some C is A; (3) Therefore, some C is B. There are
here three ‘categorical propositions’, containing only three terms (A, B and C),
with each of the terms appearing in two statements. (By comparison, ‘inductive
logic’ involves reasoning from particular statements to a general truth.)

The rules of logic are precise, inflexible
and systematic. They are, therefore, incapable of modification to suit particular
circumstances. ‘Logic with a changing content’ is a contradiction in terms. To
seek to modify the rigid rules of logic is as unproductive as an attempt to
solve a problem in terms of Euclidean geometry by ‘changing’ Euclid’s
fundamental propositions. Hence, syllogistic reasoning is not always adequate for
the representation or solution of a problem in English law, and, save for some
trivial matters, it is rarely possible to compress the essence of a complex
legal problem within the unyielding framework of a formal syllogism. Indeed, if
the schemes of formal logic were applicable to the analysis and
resolution of disputes, then settlement would be possible in a mechanical way
without the intervention of legal procedures. X’s dispute with Y arising from Y’s
alleged invasion of X’s property rights might be resolved swiftly and correctly
by reference to an exact, immutable system of logical propositions. It is
precisely because this cannot be done that the process of adjudication
becomes necessary. This is not to say that the use of ‘reasoning’ has merely a
minor role in the legal process. But ‘reasoning’ and the application of formal
logic must be differentiated. Thus, a judicial decision which is clearly
‘unreasonable’, that is, irrational, will not stand – a principle enunciated in
Associated Provincial Picture Houses Ltd vWednesbury Corp (1948);
a finding which ‘flies in the face of the facts’ would be difficult to sustain.
This is far removed, however, from situations in which purely formal logic is
used in the solution of a problem. Strict logical rules cannot be utilized to ‘make’
decisions in English law, if only because the disputed facts are often
imprecise and ‘untidy’ and cannot be presented in the exact form required for
the exercise of those rules. Thus, in a decision of the House of Lords (Hammersmith
and Fulham LBC vMonk (1991)), the question was whether a periodic
tenancy held by two or more joint tenants was determinable by a valid notice to
quit given by one joint tenant without the knowledge or consent of the other(s).
The facts were not always precise and the House did attempt to reason from
ordinary contractual principles. But the train of logic which had led from
consideration of one precedent to another and which did suggest that one joint
tenant could validly end a tenancy, was halted when reference was made to
a statement to the contrary in Howson v Buxton (1928). This was considered
and rejected as having ‘insufficient weight’. Other matters than purely logical
principles have to be taken into account.

References are made occasionally within a judgment to the significance
of logic, but generally within a wider context, for example, public policy,
social concerns. In R v Gotts (1992), the House of Lords decided that
duress was not available as a defense to a charge of attempted murder.
Lord Jauncey asked: ‘Is there logic in affording the defense of duress to one
who intends to kill but fails, and denying it to one who mistakenly kills
intending only to injure? ... I can see no justification in logic, morality or
law in affording to an attempted murderer the defense which is withheld from a
murderer.’ It is of significance, however, that these remarks were preceded by
reference to ‘the pervading climate of violence and terrorism’. Lord Jauncey
was placing his reference to logic within a setting of social facts and
desirable policies. Similarly, in R v R (1991), in which the House of
Lords decided that a husband could be criminally liable for raping his wife,
the matter was approached by means of a logical interpretation of the word
‘unlawful’ as used in s 1 of the Sexual Offences Act 1956, and s 1 of the
Sexual Offences (Amendment) Act 1974. But it was preceded by an important
observation on historical and social change: the status of women had changed in
recent years out of all recognition, so that marriage is to be regarded now as
a partnership of equals. Again, purely logical reasoning is taken into account together
with interpretations of social realities.

The use of ‘reasoning by analogy’ which is prevalent in English law and
which, if it is to be in accord with the rules of formal logic, demands the
application of rules in exact style, illustrates a general departure from the
strictness of those rules. Analogy arises from a process of arguing from
similarity in known respects to similarity in other respects. ‘Running a
country is like running a ship – the crew must obey the captain’ – here is an analogy
involving perceived similarities. Cast in formal terms, argument by analogy may
be stated thus: ‘X has certain elements, P, Q and R. Y also has elements P, Q
and R. But X also has S. Therefore, Y has S.’ The analogy may be utilised so as
to promote the understanding of a legal concept by indicating similarities between
that concept and others that may be more familiar or more readily grasped.
Argument by analogy has been used in English law to support, for example, the
concept of the right of the State to interfere so as to prevent breaks in ‘the
seamless web of the law’ in relation to breaches of conventional morality. The statement
of Lord Simonds in Shaw v DPP (1962), suggesting the existence of a
residual power in the courts of law which can be used to guard the State
against attacks ‘which may be the more insidious because they are novel and
unprepared for’, stems from an analogy between the defence of the state by its
‘guardians’ and the defence of morality by the ‘guardians of the law’. Specific
criteria of formal rules relating to analogy (for example, ‘the greater the number
of elements shared by X and Y, the stronger the conclusion’, or ‘as the dissimilar
elements between X and Y increase, so the conclusion is weakened’) tend to be
neglected in legal arguments based on analogy. Critics have pointed to some of
the decisions in ‘causation cases’ (in particular, R v Jordan (1956) and
R v Blaue (1975)) as having resulted from false analogies between the
laws of physical causation and the type of causation perceived in the facts of
these cases.

Some jurists have suggested that the unwillingness of English lawyers to
follow rigidly the principles of formal logic may be a sure guarantee of
continuing inconsistencies in the law. They point, for example, to the
continuous ‘lease or licence’ saga in land law, exemplified by Facchini v
Bryson (1952), Somma v Hazelhurst (1978), and Street v Mountford (1985),
and argue that, had the concept of a lease been applied in strictly logical
fashion to a consideration of the facts in these and similar cases, uncertainty
and inconsistency might have been avoided. (The continuing inconsistencies may
be perceived in Mehta v Royal Bank of Scotland (2000) and Bruton v
Quadrant Housing Trust (1999).) Holmes’ comments on the question of
consistency in law are pertinent: the law, he declares, is always approaching
and never reaching consistency. ‘It will become consistent only when it ceases
to grow.’ Pound reminds jurists that so called ‘scientific legal systems’,
dominated by strictly logical reasoning, will result in the ‘petrifaction’ of
law and the stifling of independent consideration of new problems and of ‘new
phases of old problems’. Jurists who support the stance of Holmes and Pound
have noted that the principles of formal logic were not responsible, for
example, for the vital changes in the law of torts effected by the enunciation
of the ‘neighbour principle’ in Donoghue v Stevenson (1932), or the important
development of the ‘proximity test’ in Alcock and Othersv Chief
Constable of S Yorks Police (1991), or the articulation of the so called ‘Bolam
test’ in relation to standards of skill to be expected from professional
persons (Bolam v Friern Hospital (1957)).

Others argue that law based on systematic logical principles will
enlarge control over the increasing diversity of legal situations. ‘It is like
fishing with large nets rather than single lines.’ Cohen, in an examination of
the place of logic in the law, suggests that this argument ignores the
important differences between the natural sciences, in which logic is
essential, and the legal order, which involves matters which are neither as
definite nor as rigid as those of the physical order. The facts of the physical
order allow highly exact description (for example, in quantitative terms); the
facts of the legal order can almost always be disputed and disregarded as wrong
in principle. ‘The specific gravity of mercury is 13.6’ is a statement which,
in terms of its logical derivation, is on a different level from that occupied
by the statement, ‘the court finds for defendant’. Cohen warns that, like some
other useful instruments, logic can be ‘very dangerous and it requires great
wisdom to use it properly ... A logical science of law can help us digest our
legal material, but we must get good food before we can digest it’.

Dewey, jurist and logician, urges caution in the face of arguments
advocating a more intensive application of syllogistic logic to legal
questions. He notes that the syllogism implies that thought or reason has fixed
forms of its own, ‘anterior to and independent of concrete subject matters and
to which the latter have to be adapted whether or no’. This is to put the
activity of rigid demonstration before that of search and discovery and
to fall into the trap of accepting that for every possible case which might arise
in the legal system, there is a fixed antecedent rule ‘already at hand’. The
result is to produce what Pound terms ‘a mechanical jurisprudence’; it flatters
the human longing for certainty. Thinking derived from a consideration of premises
is, in itself, not to be condemned; the problem for the jurist is to find statements
of general principle and particular fact which are worthy to serve as premises.
Hence, Dewey concludes, either logic in legal thinking must be
abandoned, or it must be logic relative to consequences rather than to
antecedents – ‘a logic of prediction of probabilities rather than one of
deduction of certainties’.

The difficulties of relying solely on formal logic in a search
for solutions to problems of jurisprudence and to cases arising within the
legal system are obvious. The danger may be, however, in the total rejection
of logic as a tool in legal reasoning. In Cohen’s phrase, law without
concepts or rational ideas, law that is not logical, is like pre-scientific
medicine. Lord Devlin, too, warns: ‘The Common Law is tolerant of much
illogicality especially on the surface; but no system of law can be workable if
it has not got logic at the root of it’ (Hedley Byrne v Heller (1964)).

It is of interest to note, however, that attempts have been made to cast
some aspects of legal thought and practice into patterns of strict logical (and
algebraic) terminology. Kolm has presented his arguments for ‘pure distributive
justice’, in the form of mathematical and formal logic. D’Amato has sought to
convey the essence of Austin’s thought through the medium of cybernetic models
reflecting the logical interconnections of Austin’s command theory of law.
Judge Learned Hand (1872–1961) has summarised, in his ‘Hand formula’, a logical
expression of the results of many American cases involving matters of basic negligence
standards. He expresses his logical argument in algebraic terms. Let the
standard of care be considered in terms of three variables: P (the
probability of harm resulting to the claimant from any act or omission by the
defendant); L (the gravity of the resulting harm or loss); B (the
cost or burden of preventing the harm or loss). Then consider the expression B
< PL, that is, in the words of Judge Posner, ‘If the burden to the
injurer of avoiding the accident was less than the loss if the accident
occurred, multiplied by the probability that it could occur, then the injurer
is negligent’. The formula is explained and illustrated in Conway v O’Brien
(1940).

The school of jurimetrics,
which seeks to apply to legal problems the techniques of logic, an elementary
calculus of legal probability and the utilisation of computer techniques, in
the name of its slogan, ‘A scientific jurisprudence for a scientific age’, has
had very limited success, particularly in handling the problems of the
qualitative judgments which figure large in our law. In Posner’s words: ‘We
have in law the blueprint or shadow of scientific reasoning, but no edifice.’ A
jurisprudence in which scientific formal logic replaces legal reasoning would appear,
at the moment, to lie, in Celan’s phrase, ‘well north of the future’.

Notes

The rules of formal logic may be found
in Fundamentals of Logic, by Carney and Scheer. Bodenheimer considers
law and scientific method in Chapter 17. Dewey examines the problem in ‘Logical
method and law’ (1924) 10 Cornell LQR. Cohen’s article, ‘The place of logic in
the law’, appears in Law and the Social Order. A lucid account of basic
problems related to logic and the law is given by Levi in his essay, ‘The nature
of judicial reasoning’, in Law and Philosophy, edited by Hook, and by
Posner in ‘Law as logic, rules and science’, in The Problems of
Jurisprudence.